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velope. But suppose this envelope be ruptured, or softened, so that nutrient matter obtains more ready access to the living matter within, what happens The germinal or living matter rapidly increases, and may even grow at the expense of the softened envelope itself. Masses of living matter are formed in gre number, divide and subdivide, and perhaps multiply enormously, forming a sof mass, which may continue to increase for a time, but is incapable of lasting The conditions favourable for the regular conversion of the outer particles of each mass into formed material are not present, and the whole mass may die and undergo disintegration and removal. Very many changes occurring in tissues in disease may be explained by these views. The power of living matter to grow infinitely is restricted by the conditions under which it is placed. Normaily, growth may be slow; but if the restrictions be to some extent removed, then an abnormal freedom of growth may directly occur. This is exactly what happens in the process of inflammation. The germinal matter of the normal cells is more freely supplied with nutrient matter, and this often depends upon actual rupture of the envelope of formed material. These views, it will be observed, explain the phenomena of nutrition, growth, secretion, &c., without supposing any peculiar attractive power in the cell-wall, or any mysterious agency in its structure or in the nucleus; indeed, the existence of the cell, as it is generally defined, is dispensed with altogether. The author's "cell" is a mass of living matter surrounded by matter which had ceased to live, and which, like other inanimate matter, may be changed by physical and chemical agents. He reduces "the action of the cel to the motion of living particles from centres where they become living, their passing through definite stages of existence, and their being ultimately resolved into substances exhibiting special properties, but lifeless. So he would explain the phenomena of inflammation, without resorting to the hypothesis of irritation, exaggerated action from external stimulation, &c.

According to the author's view, the most wonderful changes occur at the moment when the pabulum reaches the living centre, where its properties become completely changed, and where it commences its new course of existence. To account for the new powers which the particles have acquired, the author is compelled to assume the existence of a special force or power which can only be derived from particles which already possessed this power. He assumes that this power compels the elements of the pabulum to take up new and forced relations to each other, while, as they gradually cease to be under its influence, the elements resume their ordinary attractions, and special compounds are formed the nature of the compound depending, therefore, upon the relations which the elements were constrained to take up during the living state. Hence he maintains that vital power exists in the particles of living or germinal matter, while the formed matter around this is destitute of vital power, and is only influenced by physical and chemical forces; and he thinks that while matter is in the state of living or germinal matter, it is in a temporary condition which is distinct and peculiar, and cannot be compared with any other state in which matter is known to exist. It is very remarkable that matter in this temporary condition exhibits the same appearance in all living beings, and possesses constantly an acid reaction. When set free, a mass always assumes a spherical form, and the smallest particles to be seen are still spherical. No one could distinguish by microscopical examination the "germinal matter" of one tissue from that of another, nor the germinal matter of one of the lowest, simplest organisms from that of man. And yet, although the germinal matter of all structures appears to be the same, it differs most wonderfully in power as seen in the results of its life. The formed material, on the other hand, exhibits, as we all know, differences of structure easily demonstrated, and differences of property familiar to every one; these differences being due to vital powers existing in the matter when in its previous state of germinal matter.

Some additional Observations on the Coloured Fluid or Blood of the Common
Earthworm (Lumbricus terrestris). By JOHN DAVY, M.D., F.R.S., &c.
In this paper, supplementary to a former one on the same subject, the author, by
varied experiments, some made in vacuo, some made in different gases, has en-

deavoured to prove that the red fluid of the Earthworm is a receptacle for oxygen, and is thus subservient to the aëration or respiration of the animal.

Some Observations on the Vitality of Fishes, as tested by Increase of Temperature. By JOHN DAVY, M.D., F.R.S., &c.

The experiments described by the author were made on eleven different species of fish of our lakes and rivers, of which the several kinds of Salmonida were of the number. The results were that a temperature of water between 80 degrees and 100 degrees was fatal to each kind. The Salmonidae were those which were most readily affected by elevation of temperature, the other species bearing it according to their kind somewhat better. The results generally were pointed out as of some interest in relation to the habitats of different kinds of fish, and also as tending to prove that the accounts given by travellers of fishes existing in hot springs are exaggerated, and not founded on accurate observation.

On the Question whether the Oxide of Arsenic, taken in very minute quantities for a long period, is Injurious to Man. By JOHN DAVY, M.D., F.R.S., &c. In this paper the author gave an account of a small mountain stream in Cumberland, Whitbeck by name, which contains a minute quantity of arsenic, and which has from time immemorial been used by the inhabitants of an adjoining village, without any marked effect, either bad or good, on man and other animals, with the exception of ducks, to which birds the feeding in it has proved fatal. The author attributed the innocuity of the stream to two circumstances: first, the extremely minute quantity of arsenic present; and, secondly, the little tendency that arsenic has to accumulate in the organs of animals-the duck probably having less eliminating power than others. He mentioned instances in which arsenic in equally small quantity, derived from rivers in the Lake District, had proved fatal to the charr. He presumed that arsenic exists in many other streams, the water of which is used with impunity, the arsenic being derived from arsenical pyrites, a very common mineral, by the action of air and water, and, as in the instance of Whitbeck, comparatively harmless, and this owing to two circumstances-the very slight solubility of the oxide in cold water, and the fact of the harmlessness of the oxide in infinitesimal quantities.

Some Observations on the Coagulation of the Blood in relation to its Cause. By JOHN DAVY, M.D., F.R.S., &c.

These observations were chiefly made to test the hypothesis brought forward by Dr. Richardson, that the coagulation of the blood mainly depends on the escape of ammonia. The many results described by the author were opposed to this view. First, he showed that blood in its healthiest state contains no appreciable quantity of the volatile alkali; and, secondly, that ammonia added to the blood in a notable quantity did not arrest the change. Other experiments were described of a confirmatory kind.

The conclusion finally arrived at was that we are still ignorant of the cause of the phenomenon, and that the hypothesis of Dr. Richardson, if acted on in medical practice, must be attended with risk.

Remarks on the Loss of Muscular Power arising from the ordinary Footclothing now worn, and on the Means required to obviate this Loss. JAMES DOWIE.

By

In wearing rigid-soled boots or shoes, the waste of muscular power is of a threefold kind: first, that arising from atrophy, in which the locomotive function of the muscles of the extremities is reduced below its normal standard; second, that arising from the extra force exerted in bending comparatively rigid clothing; and third, that arising from the normal functions of the muscles of the feet when walking being partially or wholly transferred to those of the pelvic region or upper

parts of the body. In each case the sacrifice sustained is shown to be manifes The remedy proposed to obviate this threefold loss is the ingrafting of elasticated leather into the sole of the boot or shoe, between the heel and tread, under the instep, whereby the foot is allowed to perform with comparative freedom its nat, ral movements in progression, and consequently the muscles to retain their norma health, strength, and usefulness. The soundness of this conclusion is confirmed by upwards of twenty-five years' experience in the wear of foot-clothing this made. The elastic principle is shown to be a sine quá non,—mere form, however adapted to the foot when in repose, being inadequate to obviate the loss of muscular power when walking. In illustration of the elastic principle, two strong Blucher boots were exhibited, the one made on Mr. Dowie's plan, having elasticated leather ingrafted into the sole, in contrast with the other, a rigid-soled "sealed-pattern regulation boot" as now worn by the British army.

On Pearls; their Parasitic Origin. By ROBERT GARNER, F.L.S. The author said he had particularly examined those formed in the mantle of the Conway and Lancashire mussel,-not the beautiful pearls of the Alasmodon, from the Upper Conway at Llanrwst, but those of the salt-water mussel: however, he attributes the same origin to all pearls, the oxidation of a minute species of Distoma causing their formation, much in the same way that galls are formed in plants.

On an Albino Variety of Crab; with some Observations on Crustaceans, and on the Effect of Light, By ROBERT GARNER, F.L.S.

In four species of Crustacea which were observed, a splitting of the fore-claws at the third joint from the extremity took place during moulting, exactly as described by Reaumur, the line of splitting being afterwards with difficulty perceived in the cast shell. This splitting always takes place in the same line-a line noticeable in the shell of a crustacean not about to moult, at least in those species observed, as the Hermit-lobster. The author has rarely failed to detect the Nereis bilineata st the posterior part of the spire of the shell which is occupied by the latter animal, and many years back forwarded it to Dr. Johnston, of Berwick, to whom it proved an acquisition, and who believed it to be absent or rare on the Northumberland coast. The little living Cancer pagurus exhibited was found in the root of a Fucus, and when fresh moulted, which had happened several times during the last year, was white except the ends of the claws. With respect to the action of light, the author observed that some Actiniæ did not dislike it, whilst to others it was extremely distasteful; for instance, Act, dianthus to avoid it frees itself from its attachment and swims away like a Limnæus with its base to the surface, whilst the common Actinia seems to like it. As an example of the effect of obscurity on a vegetable, the author showed a curious specimen of the Clavaria form of Polyporus squamosus, which sprung from a piece of oak in an obscure part of an iron-forge. The Nereis above-mentioned seems sensible both to light and sound. The Crustacea in which the valve-like split (if split it can be called) was observed, were (besides the Hermit-lobster) the common and the shore crab, and the hairy Por

cellana.

The Skull-sutures in connexion with the Superficies of the Brain.
By ROBERT GARNER, F.L.S.

If the mammalian skull may be considered as formed by the enormous development of the elements of several vertebræ, and if the vertebral medulla in fishes gives indications of its being composed of separate ganglia, then analogy would lead us to look in the brain for separate ganglia corresponding to as many vertebræ as form the skull, and also to expect corresponding dispositions in other respectsas regards nerves and their exit, the ventricles, and the form and distribution of the internal grey matter-all probably to be traced.

However, we now confine ourselves to those parts peculiar to the brains of the higher animals-the convolutions. These are not merely chance forms due to the errant meandering of arteries and veins; for though organs are built up by arteries,

they are formed upon a preceding plan. The gyri or convolutions have a known disposition, corresponding more or less on each side in all brains, so that it is possible to trace out on paper what course the convolutions of a healthy brain will take-at any rate, the exceptions will be in small particulars; and this not in man only, but more easily as we descend through the inferior forms-the savage, the idiot, the chimpanzee, the monkey, the carnivora, and so on.

That portion of the skull occupied by the cerebrum proper may be divided into five surfaces-an ethmoidal, lodging the olfactory lobes, small in man, but ample in other mammalia, as the marsupial or elephant; a sphenoidal, to which the grey matter about the optic commissure and the island of Reil correspond; a frontal for the anterior lobes of the brain, temporal surfaces for its inferior tuberosities; a parietal for the vastly predominant superior middle portion; and an interparietal, corresponding to the posterior lobes.

Wishing to see exactly what gyri or sulci correspond to the sutures which divide the regions of the skull, and finding that this cannot by ordinary comparison be well done (our present modes of examination giving us anything but clear ideas of the topography of the encephalon), the author devised a plan of piercing the skull along the sutures, and marking the corresponding points of the brain by vermilion introduced by means of a grooved needle. He then extracts the brain, and lets it fall into a strong solution of corrosive sublimate, which has the effect of rapidly hardening it so that it will allow of a perfect cast being taken from it. The membranes may also be easily removed, though with more difficulty over the posterior lobes. Pins are introduced into the brain at the spots where the vermilion punctures are seen previous to taking the mould, which should be formed of two applications of the liquid plaster, the first most fluid and of little bulk.

With respect to the coronal suture, which appears to trend backwards in the greatest degree in the lower races of man, it will be found to correspond to a certain describable line. This begins before the first convolution above the commencement of the fissure of Sylvius, and rises, not along the oblique fissure of Rolando (separating the first from the second of those three remarkable oblique convolutions arising from the upper lip of the Sylvian fissure, and going upwards and backwards to the vertex), but more directly upwards, and more in front, before the anastomoses which the anterior oblique convolution has with the frontal ones. These frontal convolutions evidently run in a longitudinal direction in the adult, but more evidently so in the foetal brain, well marking the frontal portion. Within the longitudinal fissure the separation of the frontal and parietal portions is commonly well marked in man, monkeys, and the lower mammalia.

The squamous suture corresponds to the fissure of Sylvius, which, as far as the external surface of the brain is concerned, may be said to commence about the summit of the great ala of the sphenoidal bone, which in some skulls (prognathous ones) does not always reach to the parietal bone.

A suture occasionally exists in the occipital bone, marking the posterior edge of the brain, apparently common in the American races, but not peculiar to them, as was seen from photographs of a Negrito and other skulls, illustrating the paper in this and other points relating to the skull, and kindly lent by Dr. J. Barnard Davis. This interparietal bone (the cerebral portion of the occipital) appears to be worthy of study; it is large in the inferior races of man, and also full in the female. The lambdoidal suture corresponds to the line which divides the convolutions forming the third lobe from the middle or parietal—a line commonly well marked on the brain surface, though not an uninterrupted sulcus; more strongly in the Quadrumana, but still more strongly internally in the longitudinal fissure. The inferior tuberosity of the brain is most intimately connected with the posterior lobe.

The parietal portion of the upper surface of the brain constitutes, of course, by far its largest region. Before, are some gyri already mentioned as being anastomoses of the anterior oblique parietal convolution with the frontal. These anastomoses, in combination with the inner frontal convolution, form in man a broadly halberdshaped figure, the coronal suture crossing at a little distance before the handle as it were, but in many mammalia a broader trilobed figure like a club of cards or a fleurde-lis. Behind, we have already described three more or less well-marked convolutions going from the fissure of Sylvius upwards and backwards to the middle line,

The middle one is always the most remarkable, and a fixed point for measurement; its termination in the longitudinal fissure is marked by a deep sulcus, forming the anterior boundary of a quadrangular surface, of which the posterior boundary is the sulcus already mentioned as marking the division of the posterior from the middle lobes of the brain. The oblique convolutions (with or without the anterior one, and with or without some anastomosing gyri going backwards from the middle to the posterior lobe) form a remarkable broadly triangular or rather bat-shaped figure, more remarkable still in the Quadrumana, and reminding us of the bat-like expansion of the sphenoidal bone below, and its corresponding cerebral surface. This, of course, is merely an accidental resemblance; but where we are not sufficiently advanced to make physiological divisions, such comparisons may be of use in studying “a mighty maze, but not without a plan," and fairly belong to topographical anatomy; serving, like language, to embody our observations, and eventually, conjoined with the comparison of the internal structure, or more definitely the course of the divergent prolongations of the medulla oblongata through the brain, leading to large results.

On the Physiological Effects of the Bromide of Ammonium.
By GEORGE D. GIBB, M.D., M.A., F.G.S.

After dwelling generally upon bromine and its salts, the author referred to the alleged properties of the bromide of potassium. This salt he had used, and it failed to produce what had been asserted of its powers. He had, however, changed the base to ammonium-the bromide of ammonium-carefully prepared in a pure form by Messrs. Fincham, of Baker Street, London; and on submitting a number of healthy persons to its use, a series of highly important results were obtained. These were detailed at some length, and the experiments described. The latter were not yet complete, but the author thought them still sufficiently important to bring before the Association.

The great tegumentary systems, both internal and external,were chiefly influenced by this agent, especially the former. The adipose structures came next under their influence. Its effects on the skin justified its being considered a cleanser and beautifier of the complexion. It restored secretion to the mucous membrane, and according to the mode of its administration and the susceptibilities of the individual, so did it produce anæsthesia, especially noticeable in the fauces and throat. The membrane of the nose, the pharynx, the larynx, and bronchi, as well as that of the eyes and ears, were subject to its influence; and in the course of his experiments, the author found that the entire tract of the genito-urinary and gastro-pulmonary mucous membrane was occasionally, not always, brought under the control of this agent. It also exerted a peculiar and specific effect upon atheroma and fat; and if administered sufficiently long, and in proper quantities, it will slowly remove corpulency and allied states through the blood. Fatty changes in certain organs, such as the heart and its vessels, are arrested by it; and the author believes it would equal, if not surpass, the Fucus vesiculosus in some of its alleged virtues. The author intended to continue his investigations.

On the Normal Position of the Epiglottis as determined by the Laryngoscope. By GEORGE D. GIBB, M.D., M.A., F.G.S.

After some remarks upon the various hypotheses which have been brought forward by physiologists on the mechanism of the voice, which the author considered somewhat conjectural from the absence of ocular proof, he referred to the introduction of the laryngoscope as likely to determine the true nature of phonation and other phenomena connected with the larynx. Whilst not unmindful of this himself, he had devoted some attention to the inspection and study of the parts above the glottis, especially to explain anomalous sensations there experienced. For this purpose he had examined the throats of healthy persons with the laryngoscope, so as to become familiar with the parts in them. Up to the date of his communication he had examined 300 individuals, and his results were confined mostly to the condition and position of the epiglottis, which were so important that they had led him to form certain conclusions.

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